I just wanted to share that my DD left gymnastics this past September. She had great success all the way through Level 7, then began having fears/anxiety as an 11 year old Level 8. Frequent breaks due to covid, age/growth and chronic hip pain also negatively impacted things.... In any event, it was nearly two years of angst before she finally said she was done. In my experience, gymnasts don't ask to quit gym lightly. It is part of their identity, and often their best friends are in the gym. It's hard to say good-bye to all of that, so when they say they're ready to go, they're probably ready to go.
It was unexpectedly hard for me to let go of gymnastics. Honestly probably harder for me, then for her. I really just loved watching her....
BUT, she is happy. She's involved in two new sports (competitive climbing and diving). She has her first dive meet (competition?) next month, and is looking forward to diving for her high school next year. She has more time for school friends at a time when peer socialization is very important. She has more time for school work. She sleeps more. She eats better (not in the car). And our mother/daughter relationship is no longer stressed due to gymnastics related conflict (although there is, of course, plenty of normal teen stuff!)
Good luck. It's ok to feel sad (there are so many good memories and friends associated with gymnastics). But you should also feel proud that your daughter is advocating for herself and her needs. (PS - There is enough overlap with cheer and gymnastics, that your daughter could conceivably go back to gym later. Also, she might like a T&T program if there are any in your area?)